Some 12,000 years ago, the first human migrants to California found a rich and diverse flora of about 5000 different species of vascular (“higher”) plants. Some 1500 of these exist only in California and are termed endemic species. But many of the others were already familiar to the immigrants and they knew how to use them (or closely related species) for food, medicine, and crafts. The abundance of plant and animal foods in this environment led to the buildup by 1800 of an aboriginal population of over a half million, one of densest in the US. It also led to the development of a peaceful people who did not have to travel far nor compete fiercely to meet their needs. Although these people intensively managed their environment, to enhance the production of useful plants, they did so mainly using fire, obsidian knives, or pointed digging sticks. The result was a self-sustaining life style that did not alter or degrade the landscape.
This article will discuss some of the most important plants of the Sacramento Valley and how they were managed by the native Americans.
Figure 1. Valley Oak leaves and acorn.
The most important food source for most natives was the acorn of Valley Oak (figure 1), Quercus lobata. Over 50% of their caloric intake was satisfied by acorns, particularly during the fall and winter. Because of a high fat content (figure 2) acorns were a welcome addition to an otherwise low fat diet. Since these oaks only produce a good crop once in three years, large acorn storage granaries were built close to the homes which could hold a two-year supply. These were huge woven baskets made from grape vines and willow branches attached to a stump or posts and well thatched to keep the rain and pests out. The supports were coated with pine pitch to deter ants and weevils and layers of well-dried acorns were separated by leaves of Bay Laurel and Mugwort which have insect-repellent properties
Figure 2. Chemical composition of plant foods (%);
CHO means carbohydrate.
From Blackburn and Anderson (1993).
| Food | Water | Protein | Fat | CHO |
| Valley Oak (acorn flour) | 8.7 | 4.8 | 18.6 | 65.9 |
| Black Oak (acorn flour) | 11.3 | 3.8 | 19.8 | 64.8 |
| Foothill (Gray) Pine (seed) | 3.6 | 25.0 | 49.4 | 17.5 |
| Wheat Flour | 12.0 | 13.3 | 2.0 | 71.0 |
The September harvest of the acorns was a major event and was accompanied by rituals involving giving thanks to the trees as valuable ‘givers of life’. First, the area under the trees belonging to the family group was burned to get rid of trash that would impede the harvest and to remove old, insect infested acorns. Young men climbed the trees or knocked the green acorns with long poles from the ground. Women, with conical burden baskets held by a band across the forehead, expertly tossed the nuts over their shoulder into the basket. Since over 100 pounds could be collected in an hour, a few days were sufficient to gather a year’s supply. These were immediately dried, because the moist nut forms a rich substrate for Penicillium and Aspergillis fungi. During the knocking of the acorns and the burning beneath, many branches were removed and the trees ended up being shaped much like a modern day orchard.
The dried acorns were backpacked home and put in the basket granaries. Each day several quarts of nuts were removed, the hulls pried off, and the embryos pounded in a mortar using a rock pestle to form a fine powder. Ten or more changes of cold and then hot water were poured through the acorn flour until the bitterness from the oak tannins (‘tannic acid’) was gone. Unleached acorn meal is so poisonous because of the tannins that several meals of it would result in cirrhosis of the liver and a painful death. What occurs is that the tannins combine with protein enzymes and cell membranes of the digestive tract inactivating them–essentially ‘tanning’ them, that is, turning them into shoe leather!
The wet acorn dough was then placed in a cooking basket along with water to make a mushy porridge. Hot rocks the size of a fist were stirred in until the meal was cooked. It was eaten by dipping in with several fingers and sucking off the bland mush or by using a seashell. Alternatively, the mush might be placed on hot rocks to make a little pancake or wrapped in leaves (Soap Plant, Poison Oak, etc.) and placed in an underground, rock-lined ‘oven’ to produce a hard loaf.
Since tannins attach to and change proteins, they can be used to destroy bacteria and fungi; indeed, their high concentration in bark helps protect the tree from disease. The Indians frequently used tannin eye washes and salves to combat infections. The European pioneers had another interesting use for tannin–they produced a long lasting black ink! They used green oak galls (tumors induced by chemicals secreted by gall wasp larvae) as ink wells; the chemical reaction between the iron from a pen poked into the juicy gall and the tannins resulted in an excellent ink. Incidentally, in late September the galls can be placed in a container and the tiny, harmless gall wasps can be seen emerging.
Since Valley Oaks require six feet or more of loamy soil, with moisture available below that, most of them were removed and replaced by orchards. Unfortunately, with them went a rich habitat for hundreds of species of insects, birds, and animals. The few acres that remain must be protected from grazing and allowed occasionally to burn in order to have the acorns germinate and produce young trees. Only then will that habitat be restored.
Figure 3. Blue Oak leaves and acorns.
Blue Oaks, Quercus douglasii, live in the foothills on shallow, well-drained soils (figure 3). They produce a good crop only once every four years and the quality of the acorns is not quite as good as the Valley Oak. They possess physiological and anatomical features that allow then to survive long periods of drought–conditions that would kill the Valley Oak. Where the two species meet, vigorous hybrids that are intermediate in appearance are occasionally produced.
Figure 4. Black Oak leaf and acorn.
Black Oak, Quercus kelloggii, is found above the Blue in the Mixed Coniferous Forest plant community (figure 4). The presence of a root crown with lots of buds allows it to survive fire that removes its competitors–Douglas and White Firs. Since its acorns have a high fat content, it was prized by the Indians and acorns were traded over long distances.
Interior Live Oak, Quercus wislizenii, is common in the foothills and its acorns were heavily used as were those of the Canyon Live Oak, Quercus chrysolepis, which is found in the canyons leading from the valleys. Closely related to these true oaks is the Tanbark ‘Oak’, Lithocarpus densiflora, whose acorns were highly rated by many Indians perhaps because they had a high fat content and because they stored well due to their very high tannin content.
Pinus sabiniana (figure 5) lives alongside the Blue Oak and regularly produces many large cones weighing 2 to 4 pounds. On each cone scale, two seeds are located each one-half an inch long. The cones were knocked to the ground in the fall and heated to release the seeds. These were stored in baskets in the dwellings or in caches underground. The seeds were cracked open, as needed, and the delicious pine nuts eaten raw or roasted.
Figure 2 shows that the pine nuts were extremely nutritious–much like peanuts. They were given to guests as a welcoming treat or taken on journeys as light-weight, high energy food. Mashed pine nut was diluted with water and fed to newborns as their first food.
The pliable roots were dug up with digging sticks and woven into conical carrying baskets. Pitch from the tree reduces the growth of bacteria and was mixed with fat or wax to form a healing salve. Incidentally, at any feed store, you can buy “Bag Balm” which is used to heal cuts on livestock and has pine pitch as its active ingredient! A dwarf mistletoe which grows on the tree was used as a contraceptive. And the hard-shelled seeds were strung as beads to form a handsome necklace.
Ground and tree squirrels along with scrub jays and acorn woodpeckers compete vigorously for this rich supply of food, beginning in early August–long before the cones are even ripe. Without the jays, however, the pine woodland would disappear for they carry seeds up to 8 miles and bury them for winter food thus spreading the species.
Figure 5. Foothill (Gray) Pine. Bundle of 3 needles, and cone.
Umbellularia californica (figure 6) is known along the coast as “Pepperwood” and across our northern border as “Oregon Myrtle”. The glossy, 4-inch leaves and the green, pungent fruits contain a peppery oil which was extensively used medicinally and also as an insect repellent. The leaves (oil) were rubbed over aching or arthritic limbs as a stimulating and warming liniment which also exuded a pleasant fragrance. We use a leaf in stews or spaghetti as a unique spice in the place of its cousin, Grecian Laurel. Add a leaf to a jar of nuts or flour and the volatile oil will inhibit some insects; in fact, the acorn granaries were often lined with Bay.
Several bushels of the round, 1/2-inch seeds were stored and then parched in hot ashes a few at a time for an aftermeal treat. Surprisingly, they have an intriguing, if strong, flavor that made them popular.
Figure 6. California Bay Laurel. Leaves, flowers, and fruits.
All the species of Brodiaea, Triteleia, and Dichelostemma form a bulblike “corm” that is high in starch with sugar and protein also. They can be eaten raw or baked and are quite tasty–but a lot sweeter than our white potatoes. Bluedicks (figure 7) is the earliest and most common in our grasslands. The Indian women would pry the corms out of the ground in favorite places year after year using digging sticks; the latter were made from a hard wood like Mountain Mahogany, about 4-feet long, and sharpened on one end.
Figure 7. Indian Potato (Bluedicks) flowers. leaves (part), and corm.
Each corm produces a number of small “cormlets” that are attached by a fragile stem to the corm base. These clones separate easily and in the disturbed soil produce plants much faster and more dependably than by seed. You can readily imagine that centuries of harvest would result in recognizable gardens; undoubtedly, they were weeded, burned over regularly, and tended carefully by the villagers for here was a self-perpetuating source of food ready at any time of year.
Known by the Spanish as Amole, Chlorogalum pomeridianum (figure 8) produces a large bulb up to 4-inches in diameter that is entirely underground and sheathed by many brown, fibrous scales. The fibers were bundled together by their tips, glued, and wrapped to form a whisk-broom-like brush that was used to sweep the acorn flour into a pile for easy transfer to the leaching site. The glue came from the sap of the heated bulb.
Figure 8. Soap Plant with bulb and flowers.
Most important, however, was the high content of saponin–a non-alkaline, mild soap; half a bulb made an excellent bar of soap that was extensively used for bathing and washing hair. Occasionally, the villagers would mash many bulbs and dump them in a pool. The detergent would prevent fish from obtaining oxygen whereupon, becoming asphyxiated, they floated to the surface and easily gathered
The young bulbs are readily transplanted and the plant makes an interesting garden novelty. The mature bulbs send up a 6-foot tall inflorescence with many 1-inch, greenish-white flowers. The latter pop open with an audible snap (!) in the early evening. They remain open just long enough for large, black solitary bumblebees and hummingbird moths to pollinate them and then they shrivel up. Pomeridianum means “afternoon” and refers to the late time of blooming.
Muhlenbergia rigens (figure 9) is a large bunch grass that grows in moist places in the foothill woodland and riparian plant communities. The 6-foot high flowering stalks were gathered in mid-summer and used as the foundation material for the coiled baskets. To make these, several stalks were bundled and tightly wrapped with fine strands of lemonade bush branches (Rhus trilobata) or sedge rootstocks (Carex spp.), completely hiding the stalks. At short intervals, the wrapping strand is passed under the coil below it and then returned to the coil above, tightly joining the two and shaping the basket. Often it would take a year to make a large cooking basket and it was so tightly woven that it would hold water.
Figure 9. Deer Grass leaves and flowers.
The coarse leaves were not used for baskets but were shredded and used to make knee-length grass skirts. Rhizomes and young shoots were often eaten. Since thousands of stalks were needed for just one basket, patches of deer grass were carefully managed and regarded as family possessions. In order to produce high quality materials for the next year, the patch was burned each fall.
Blackburn, T.C. and Kat Anderson 1993. BEFORE THE WILDERNESS: Environmental Management by Native Californians. Ballena Press, Menlo Park CA
Heiser, R.E and A.B. Elsasser 1980. The Natural World of the California Indians. UC Press, Berkeley CA
Strike, Sandra 1994. Ethnobotany of the California Indians. Vol. 2. Balogh Sci. Bks., Champaign IL
Wes Dempsey is Emeritus Professor of Biological Sciences at CSU-Chico where he has taught since 1954.
Article reproduced, with the author’s permission, from a circular made possible by the Center for Mathematics and Science Education at California State University, Chico. One of the goals of the Center is to improve the teaching and learning of science and mathematics at all levels.
For printed copies or information, contact:
Center for Mathematics and Science Education
California State University, Chico
Chico, CA 95929-0530